1. Field of the Invention
The present invention relates to a friction drive device that is equipped a pair of rollers being pressed to contact with each other via a cam member so as to transfer mechanical power between them at a reduction ratio or an overdrive speed ratio.
2. Background Information
Some conventional art friction drive devices are provided with a wedge roller disposed between a drive roller and a driven roller, so as to automatically generate a pressing force proportional to a transmission force by maintaining the wedge roller at an angle in the direction of a tangent line at the contact point of the rollers (see, e.g., Japanese Laid-Open Patent Publication No. 2002-349654).
In view of the above, it will be apparent to those skilled in the art from this disclosure that there exists a need for an improved friction drive device. This invention addresses this need in the art as well as other needs, which will become apparent to those skilled in the art from this disclosure.